Evaluating and classifying restrictions and hydrogeomorphic hazards for sustainable urban development planning in dry areas (case study: Birjand, South Khorasan Province, Iran)

Urban, rural, and industrial regions located in natural settings need to be developed after a careful study of the natural features and hazards. Geomorphological investigations can reveal many high-risk natural hazards and limitations of such development. The aim of the present study was to investigate the hydrogeomorphological restrictions of physical development of Birjand and classify the study area based on the hazard factors. The information required for this study included a geomorphological map, morphological data, and 19 morphometric indicator layers of sub-basins in the area analyzed with GIS software. Different classes of hydrogeomorphological hazards of the area were obtained using a combination of geomorphological and hydrological features. Based on the results, 59% of the area was found to be in a moderate- to high-risk zone. The greatest risk was seen in the central parts and the southwestern end of the city. It was observed that most buildings, facilities, and communication links of the city lie in the flood-flow paths without any attention being paid to urban development limits.